LTR Coil Pack/Module resources

[wakescene]

I have a 2001 Maristar 210 with the LTR 330 motor. Over last summer I was getting an intermittent misfire on cyl 7. Again intermittent. Sometimes it happens on start up, sometimes not. Sometimes it develops when we are out boarding or wakesurfing, but not every time. They is some light shaking at idle when it happens. I was successful in restarting the motor to clear the problem on most occasions.

Everything is up to spec with the maintenance. plugs, wires, filters (incld fuel). Grounds are all good and clean etc. I am suspecting this is a coil pack issue. its the only thing I can determine.

I talked with my dealer and the coil pack comes as an entire unit for all 8 cylinders, for the silly little price of $800. There has got to be a easier way. I talked to skidim and they suggested that I pull them and maybe source them individually from Accel or GM.

Anyone played around with the coil packs on this motor and have suggestions?

I am going to pull the coil packs out and see what I can find. Maybe I can shed some light on this for others.

BTW, the boat has 900hrs entirely in saltwater. Most likely a instigator in the problem.

[wakescene]

So I did a bunch of research and talked to a few people on this. Gotta thank the people at Skidim (love them) and also the tech from Summit Racing. Both were not 100% on this stuff, but were able to assist in learning more about the topic. I am also very familiar with the late-90's GM 5.7L Vortec motor so I had some decent knowledge going into this.

(Preface: I have a 2001 MC Maristar with the LTR 330hp motor. I can only speak for this motor from about 1998-2002. Before and after this, some parts may have changed. Please check locally on your motor for info or with your dealer.)

I'll probably start a new thread on this as it's going to be loaded with information but so far in my research I have found the following:
The LTR motor was a off-shoot of the GM 5.7L LT1 & GM 4.6L Northstar motor with mods to "marinize" it. How or why they Hybrid these two engines together like this is beyond me, but it works and is a fairly easy motor to work with as long as you know what your looking for.

If your running a 1998-2002 LTR motor, there is a 99% chance the Coil Pack/Ignition Control Module is from a 1994-1999 Cadillac Deville. The coil packs themselves though are the same as you would find in many early 90's - mid 2000 model GM vehicles. They are nothing fancy and there are alternative to them (see below). The are used on a ton of GM motors, like the 4.3L V6, 4.6L V8, 5.0L V8 and 5.7L V8 motors. The differences really have to do with the ICM board that was planted under the Coil Packs.

The ICM (Ignition Control Module) is a flat plastic electronics board that the Coil Packs get attached to. The ICM has 2 male prongs per Coil Pack with Electrical connection at both ends for power, crank sensors, Tach and related electronics info going into and out of the board. (This is the most expensive part in the package).

There are a number of retail outlets to get replacements for these parts, you just have to remember that for this model motor in the years I specified above, you need to search for a 1999 Cadillac Deville to get the correct info and P/N's.

Here are some resources and some pictures to help if you need them.

GMPartsDirect.com (These are guaranteed to be correct and are OEM(read most expensive))
Bracket - Distributorless ignition- 94-99 MSRP $65.98 Your Price $34.32
Ignition Module - Distributorless ignition- 94-99 MSRP $815.08 Your Price $423.84
Coil - Distributorless ignition- 94-99 MSRP $77.16 Your Price $40.12
Seal - Distributorless ignition- 94-99 MSRP $2.08 Your Price $1.08
Screw, COI - Distributorless ignition- 94-99 MSRP $1.62 Your Price $0.84

Alternatives
(Sourced from SummitRacing.com)
Coil Pack - ACCEL
P/N = 140017
Part Type = Ignition Coils
Product Line = ACCEL AC/Delco Style DIS Super Coils
Summit Racing Part Number = ACC-140017
$ 42.95

Coil Pack - MSD
P/N = 8224
Part Type = Ignition Coils
Product Line = MSD Blaster OEM Replacement Coils
Summit Racing Part Number = MSD-8224
$ 44.95

Ignition Control Module
P/N - LX362
Summit Racing P/N - SMP-LX362
Product Line - Standard Motor Ignition Modules
Price - $225.99

Napa Online (sourced from napaonline.com)
- Ignition Control Module
Product Line = Echlin Ignition
P/N = ECH TP415
Price = 279.00

- Ignition Coil
Product Line = Mileage Plus Electrical
P/N = MPE IC39SB
Price = 26.99

- Ignition Coil
Product Line: Echlin Ignition
Comments: 4 Terminals
Per Car Qty.: 1
P/N = ECH IC39
Price = 53.49

- Ignition Coil
Product Line = Delphi Engine Management
P/N = DEM GN10123
Price = 61.99

Here are some pics of my Coil Pack unit pulled from the motor. I have pretty much determined this is a ICM issue because of some corrosion I found on the male prong for the specific cylinder I have been having problems with. I am going to try and clean up the ICM and reinstall everything (using Di-Electric grease to assist in corrosion prevention) to see how she runs. If need be, I have all the info I need to start swapping out parts to get the mis-fire problem under control.

Pictures Legend:
1st - Coil Pack/ICM unit mounted on the motor. (just follow the spark plug wires to find yours)
2nd - Coil Pack/ICM unit removed from the motor.
3rd - Coil Packs (4) removed from ICM.
4th - ICM unit.
5th - ICM prongs up close with seal removed (showing minor corrosion)

I hope this helps someone!
KG

[JimN]

That dealer is full of shyte. Also, those coils fire two cylinders at a time, not independently. It's called 'waste spark' and since a cylinder will have combustible gases in it after the combustion cycle, it's burned off while the complementary cylinder is firing and this helps smooth out the idle.

Swap the coils around and see if the problem follows that coil.

[wakescene]

That dealer is full of shyte. Also, those coils fire two cylinders at a time, not independently. It's called 'waste spark' and since a cylinder will have combustible gases in it after the combustion cycle, it's burned off while the complementary cylinder is firing and this helps smooth out the idle.

Swap the coils around and see if the problem follows that coil.

JimN, thanks for the info. Very interesting to learn and I will definitely swap around the coils and see if the problem continues. On the surface this type of work seems very daunting, but in reality there is not much that can be done with by the DIY. It's mostly parts-changing and checking connections for cleanliness.

[ahhudgins]

[QUOTE=JimN;739020]That dealer is full of shyte. Also, those coils fire two cylinders at a time, not independently. It's called 'waste spark' and since a cylinder will have combustible gases in it after the combustion cycle, it's burned off while the complementary cylinder is firing and this helps smooth out the idle.

Swap the coils around and see if the problem follows that coil.[/QUOTE]

If I had a nickel for every time a parts guy at a car or boat dealer gave me a load of crap, I'd have a LOT of nickels and a big ol' load of crap. I wonder how many coil packs they've sold for $800?! It makes you wonder if they don't know the packs can be swapped, or they just want the extra money.

[JimN]

[QUOTE=ahhudgins;739038]

That dealer is full of shyte. Also, those coils fire two cylinders at a time, not independently. It's called 'waste spark' and since a cylinder will have combustible gases in it after the combustion cycle, it's burned off while the complementary cylinder is firing and this helps smooth out the idle.

Swap the coils around and see if the problem follows that coil.[/QUOTE]

If I had a nickel for every time a parts guy at a car or boat dealer gave me a load of crap, I'd have a LOT of nickels and a big ol' load of crap. I wonder how many coil packs they've sold for $800?! It makes you wonder if they don't know the packs can be swapped, or they just want the extra money.

If they decided to only use the shotgun method of diagnosis, that obviously works for them but it's a huge disservice to their customers. People who say "just fix it" are at the mercy (or lack, thereof) of dealers like these. If they don't know the packs can be swapped, it means they don't have a trained mechanic- by MC or anyone else.

[JimN]

JimN, thanks for the info. Very interesting to learn and I will definitely swap around the coils and see if the problem continues. On the surface this type of work seems very daunting, but in reality there is not much that can be done with by the DIY. It's mostly parts-changing and checking connections for cleanliness.

It's not that bad unless there's no knowledge of electronics/electricity because, once a mechanical cause is ruled out, the only remaining cause is electrical. Or, someone cast a spell.

[rem_pss308]

I get my coil packs from Napa. they are about 20 bucks. ( local store ) You can purchase just one if need be.

[jwskier]

I actually have having ignition problems as well, on a 99 with the LTR engin. I posted a question under electric. My dealer said I had a bad ignition module, and the Indmar price was 850-1,100. I pulled it off the boat and went "googling" and found the part at summit racing. Here's the link. . http://www.summitracing.com/parts/SMP-LX362/?rtype=10 I can confirm that the part was from a cadillac!

I actually ended up buying it from Amazon, and got it for 170.00. However, I decided to clean all the connections and reinstall the old module before I put the new on one. When I got it back together, everything ran like a champ. Actually sent the part back to amazon today.

Thanks for posting the details... If i had this information, i would have saved myself several months of research. Anyway, for anybody else that has hesitation/electric/ignition problems, and you've eliminated everything else, and your mechanic says it's the ignition module, don't worry, you don't have to fork over 1K!

[wakescene]

jwskier,
Thanks for posting your experience. It's good to know Summit also has the ICM (I was not able to find it on their website, perhaps a bad search term on my part.) I'm going to modify my post to include this info.

KG

[phillywakeboarder]

Hey wakescene, I just wanted to say THANK YOU for posting all this info. I'm getting ready to replace my coils and the info you've provided has been incredibly helpful. If you have any tips on landing a wrapped heelside 5 I'm all ears . . . .

[JimN]

Hey wakescene, I just wanted to say THANK YOU for posting all this info. I'm getting ready to replace my coils and the info you've provided has been incredibly helpful. If you have any tips on landing a wrapped heelside 5 I'm all ears . . . .

Why are you replacing your coils?

[Jeff d]

I have an LTR that's running great at the moment but this is good info to have.

I was getting an intermittent misfire on cyl 7.

I'm curious how you know such specific info about the misfire. Is the dealer pulling a code for you that tells you? Or are you using what I've heard referred to as the "paperclip method" to get the check engine light to telegraph the codes to you? Also, once you have the codes where can you lookup what they mean? I'm assuming these aren't the standard automotive OBDII codes that could be looked up anywhere online.

[JimN]

I have an LTR that's running great at the moment but this is good info to have.



I'm curious how you know such specific info about the misfire. Is the dealer pulling a code for you that tells you? Or are you using what I've heard referred to as the "paperclip method" to get the check engine light to telegraph the codes to you? Also, once you have the codes where can you lookup what they mean? I'm assuming these aren't the standard automotive OBDII codes that could be looked up anywhere online.

Unless the IC module or ECM has a problem, no code will be present and it's OBD I- same codes as regular GM, when applicable.

Edited to add:

If one or more cylinders isn't firing, the knock sensor may pick up something and that could show a code. It depends on the situation.

[Jeff d]

Unless the IC module or ECM has a problem, no code will be present and it's OBD I- same codes as regular GM, when applicable.

So, if you had a misfire would you just pull one sparkplug wire at a time until the engine idles smooth? Then try swapping the coil for that plug with another one and if the problem follows the coil then you know it's bad?